我有一个 sqlite db, 数据是由一个字符串字段订购的。 我想从某个字符串字段的字典顺序中取回从某个开始的行数。 现在我使用 liMIT 查询, 但我对速度不满意。 我认为只搜索第一个, 然后告诉 sqlite 获得行数跟踪更好, 我怎么能这样做? (我的英语不好, 如果错了, 抱歉)
我不确定你的意思,但我会试着回答,如果我偏离轨道,请提前表示歉意。
考虑一下您的字符串列被称为线条。 如果您想要在用特定顺序选择时有良好的性能, 您必须在要排序的列上有一个索引 。
您的查询将看起来像 :
SELECT *
FROM mytable
ORDER BY mystring
LIMIT 5,10
这是最快的解决办法。
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